As well known in the art, recently, with expansion of IT infrastructures, power consumption in Internet data center (IDC) which operates hundreds of thousands of IT (information technology) equipments has been becoming a big issue.
Accordingly, many enterprises organized a consortium called “Green Grid Project” in April, 2005, and have researched on the power of the data center.
Especially, for construction of a low power data center called “Green Data Center”, IBM (International Business Machines Corporation) is developing, for example, a server virtualization technology, a provisioning technology, a liquid cooling system and the like. Also, DVS (dynamic voltage scaling), which is a power management technology in a operating system level for implementation of a low power platform, a request hatching technology and a simultaneous multithreading technology are being developed.
As such, a variety of researches are being performed to reduce power consumption of service platforms in a data center. For example, ‘ACPI 1.0’ was established by Hewlett-Packard, Intel, Microsoft, Phoenix, Toshiba and others in 1996, which is a standard for managing power in overall hardware and software. According to ACPI 1.0, amount of power of hardware equipments is controlled by an operating system, so that the power consumption is reduced by supplying or blocking a power source of hardware equipments depending on whether the equipments are used or not. This ACPI was applied to windows operating system for the first time, and now, many operating systems such as Unix, Linux, and free-Berkeley Software Distribution are supporting ACPI.
Moreover, a standard, ACPI 3.0b, was established in October, 2006. In present, about 20 enterprises are using ACPI 3.0b as a standard and are participating in addition and correction of the standard.
Meanwhile, as a technology for reducing power consumption in a processor which consumes the largest power among internal components of a service platform, there is a dynamic voltage & frequency scaling (DVFS) technology. The DVFS technology reduces the power consumed in the processor by controlling an operation speed and voltage of the processor. Since the processor is synchronized with a clock, if the operation speed of the processor decreases, the power consumption of the processor is reduced. Also, power is proportionate to the square of the voltage, and thus if voltage of the processor decreases, the power consumption of the processor is reduced.
As described above, various technologies for reducing power consumption of service platform are developing. However, such technologies are for managing a power source of hardware resources within a single service platform. Therefore, it is difficult to support an efficient power management in a cluster system which is mainly used by many Internet portal services companies using a data center.
In case of performing a power control of a single service platforms using ACPI, service platforms constituting the cluster system often go down or go to sleep, so that it frequently occurs that services are not smoothly provided when there are many service requests. Moreover, a complexity of a monitoring system increases, thereby costs for management the system becomes high.
In the cluster system connecting respective service platforms each other, since all service platforms operate their function best all the time, power is consumed even when the cluster system does not have a work to do. Accordingly, a necessity of power management in the cluster system arises.